"On the 2008 GTK+ Hackfest in Berlin, Imendio's GTK+ hackers presented their vision of GTK+'s future and the reasons why they think that GTK+ has to make a step forward, embrace change and break ABI compatibility. Other GTK+ developers have also voiced their opinions, listing parts of GTK+ that need serious love, but state that they don't require breakage. Whether or not these are the things that will mark the road to GTK+ 3.0, almost all of them need attention. And give hints to the shape of things to come."

Just to add my favourite: Scala (Very advanced type system, runs on the JVM, can be mixed with Java very easily, allows for booth OOP and FP styles in an interesting mix of objects and higher order functions)